December 14 marks the beginning of Audubon's annual Christmas Bird Count. The Count runs through January 5, 2013. The first Christmas Bird Count (CBC) took place on December 25, 1900 when 27 participants counted and identified about 18,500 birds, mostly in the northeastern U.S. Today, volunteers brave snow and chilly temperatures to identify and count birds throughout the 50 states and in Canada. Last year, over 2200 counts were completed and 64 million birds were reported! CBC data helps scientists understand how bird populations have changed over the past century.

Forty years' worth of observation data from the CBC show that 58 percent of North American bird species seen in the first few weeks of winter have shifted their ranges north. Sixty species have moved over 100 miles north - the wild turkey has moved a whopping 400 miles! (Learn more about range shifts of finches in the Western, Midwestern, and EasternUnited States.)

Viewer Tip: Anyone can participate in the Christmas Bird Count. CBC takes place in "count circles" that focus on specific geographic areas. Every circle has a leader, so even if you are a beginner birdwatcher, you'll be able to count birds with an experienced birder and contribute data to the longest-running wildlife census. If your home happens to be within the boundaries of a count circle, you can count the birds that visit your backyard feeder.